Abstract

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Background: As HIV-infected patients are surviving longer on antiretroviral medication, case reports of lung cancer developing in HIV patients are emerging. We conducted the present study to characterize the differences between lung cancer patients with and without HIV infection. Methods: Patients with lung carcinoma and HIV were identified at an urban hospital, Johns Hopkins, between 1985-2004 by linking the institution’s Lung Cancer SPORE and outpatient HIV clinic databases. HIV + patients with lung cancer were compared to 7,428 patients in the Lung Cancer SPORE database with unknown HIV status (mostly HIV uninfected). Results: We identified 90 HIV+ patients with lung cancer. No patient developed lung cancer before HIV diagnosis. The median interval between HIV diagnosis and lung cancer was 6 years. HIV+ lung cancer patients were younger than others with lung cancer (median age 46 vs. 63 years, p=0.001). The younger age at onset is a likely explanation for lower average pack-years of smoking observed in the HIV-infected lung cancer patients (35 versus 53 pack-years, p=0.001), despite the fact that the prevalence of smoking was higher in the HIV-infected (99%) compared to other (88%) lung cancer patients. Both groups were majority male, but differed by race with the HIV cohort being more likely to be African-American (p=0.001). HIV+ patients more frequently presented with adenocarcinoma than other patients (53% vs. 32%, respectively, p=0.02). The median CD4 count for the HIV+ patients at lung cancer diagnosis was 298 cells/ml (range 0 - 1,091 cells/ml). The median viral load was 613 copies/ml (range 0 - 750,000 copies/ml). The survival of the HIV+ group was significantly shorter than that of the non-HIV lung cancer group (median 6 vs. 9 months; p=0.002; univariate RR 1.50, 95% CI, 1.19-1.87). Late stage of disease appeared to explain the poorer prognosis among HIV-infected lung cancer patients, since after adjusting for lung cancer stage at presentation in a multivariate analysis, HIV+ and other lung cancer patients had a similar death rate (RR 1.06, 95% CI 0.85-1.34). Conclusion: We report a clinical observation of a large number of patients with HIV and lung carcinoma in a single institution. HIV+ patients with lung cancer present at a younger age and are more likely than other patients to have adenocarcinomas and more advanced cancer at diagnosis. Extensive smoking histories are ubiquitous. Survival of HIV+ patients is poor primarily due to late stage of presentation. This study adds additional evidence concerning the potential link between HIV and lung cancer.